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    welcome <i>to</i> itany <br>
    welcome <em>to</em> itany <br>
    <address>江苏省南京市秦淮区龙蟠中路458号</address>
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    跟<b>汤老师</b>学开发 <br>
    跟<strong>汤老师</strong>学开发 <br>
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    <del>Java软件开发</del>
    <ins>Java软件开发</ins>
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    跟<small>汤老师</small>学开发 <br>
    跟<big>汤老师</big>学开发 <br>
    跟<span style="font-size: 30px;">汤老师</span>学开发 <br>
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    2<sup>3</sup>=8 <br>
    水的分子表达式：H<sub>2</sub>O
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    welcome to html <br>
    <bdo dir="rtl">welcome to html</bdo><br>
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    <abbr title="Hyper Text Markup Language">HTML</abbr>



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